Britain's banks have again been warned over bonuses and lending to small and medium-sized firms (SMEs) with the top four tipped to post over £8bn in collective first half profits this week.In an interview with the Sunday Telegraph, UK chancellor George Osborne said the the government would not tolerate banks putting pressure on SMEs. "Every small and medium-sized company that I have visited in recent weeks has had some problem with their bank - either they have found it difficult to renew their overdraft or they demanded additional collateral, often someone's house," he said."The danger is that, particularly next year when there is a huge amount of refinancing required, that the small and medium-sized businesses suffer from a lack of access to working capital."Banks could also be on a collision course with the government over bonuses, especially the Liberal Democrats members in the coalition.Analysts expect Barclays to pay out 38% - 40% of income as bonuses, the highest of the UK banks. State-owned Royal Bank of Scotland's payout ratio, meanwhile, is expected to rise from 27% last time to between 30% -35% this first half.The higher payouts will reflect a strong recovery in profits at all of the banks. State-controlled RBS is tipped to make £200m, while Lloyds Banking Group is forecast to report a £800m profit.HSBC, reporting tomorrow, could report £5.5bn, whole Barclays and Standard Chartered are forecast to make £3bn and £2bn respectively.